The present invention relates in general to dispensing guns for dispensing substances contained in cartridges. More particularly, the present invention relates to an apparatus for dispensing a multiple-component substance (e.g., a two-component adhesive) from a multiple-barrel cartridge.
Conventional multiple-component adhesives typically exhibit limited pot life at room temperature subsequent to mixing. Therefore, conventional multiple-component adhesives must typically either be pre-mixed and frozen until use or mixed just prior to use (e.g., using a multiple-barrel cartridge that mixes the components of the adhesive in a static dispersion tube). In the first case, the conventional multiple-component adhesive is typically pre-mixed, packaged into a suitably sized single-barrel syringe, and frozen (e.g., xe2x88x9240 C.) until thawed for use. When ready for use, the syringe containing the pre-mixed adhesive is thawed and mounted to a conventional dispensing tool. Such conventional dispensing tools may employ, for example, an air-actuated piston or a rotary screw to drive a plunger through the barrel of the syringe. Unfortunately, such conventional dispensing tools do not accommodate multiple-barrel syringes or cartridges. Because the pre-mixed adhesive in a non-frozen state possesses limited pot life (e.g., 5-15 minutes), the pre-mixed volume must be small enough to ensure that the entire single-barrel syringe will be used without delay. This process is cumbersome and tends to result in wasted adhesive.
Alternatively, the conventional multiple-component adhesive may be mixed just prior to use as mentioned above. Typically, this is accomplished by using a multiple-barrel cartridge that mixes the components of the adhesive in a static dispersion tube. Many conventional multiple-component adhesives are packaged in a cartridge that includes multiple barrels. A dual-component adhesive from a dual-barrel cartridge, for example, may be dispensed using a conventional xe2x80x9ccaulk gunxe2x80x9d modified to receive the dual-barrel cartridge. Unfortunately, such conventional caulk guns typically include hand-operated ratchet mechanisms that do not readily permit precise placement of the adhesive bead.
Therefore, there exists a need to provide an enhanced apparatus for dispensing a multiple-component substance from a multiple-barrel cartridge.
An object of the present invention is to provide an enhanced apparatus for dispensing a multiple-component substance from a multiple-barrel cartridge that addresses these and other problems associated with the prior art.
Another object of the present invention is to provide an enhanced apparatus for dispensing a multiple-component substance from a multiple-barrel cartridge that promotes precise placement of the adhesive bead.
These and other objects of the present invention are achieved by providing an enhanced apparatus for dispensing a multiple-component substance from a multiple-barrel cartridge (e.g., a two-barrel adhesive cartridge) that includes a housing having a slot for receiving a flange of the cartridge. Preferably, the housing includes a pivoting latch that rigidly secures the flange within the slot. Plungers positioned within the housing are received by the barrels of the cartridge. A motor, which is disposed in the housing and controlled by a microprocessor, is mechanically connected to the plungers and drives the plungers within the barrels. The motor may be connected to the plungers through a lead screw assembly, for example. Preferably, the housing is handheld for ease of operation and remote from a control unit containing the microprocessor. The control unit may include a keypad and screen, operatively connected to the microprocessor, for data entry and display. The dispensing apparatus permits precise placement of two-component adhesives packaged in conventional dual-barrel cartridges, for example.